US9917481B2ActiveUtilityPatentIndex 49
Synchronous reluctance machine
Est. expiryMay 23, 2034(~7.9 yrs left)· nominal 20-yr term from priority
H02K 1/2766H02K 21/16H02K 2213/03H02K 1/246H02K 1/146
49
PatentIndex Score
0
Cited by
24
References
13
Claims
Abstract
There is described a synchronous reluctance machine having a plurality of poles and comprising a stator with a plurality of spaced slots and a rotor. The rotor has one direct axis and one quadrature axis for each pole and comprises a plurality of flux barriers, each extending to a circumference thereof at least one barrier point. Successive angular separations between barrier points around the circumference of the rotor increase or decrease when moving around half a pole pitch from an initial axis to an adjacent finishing axis, the initial axis being one of a direct axis or a quadrature axis and the finishing axis being the other of a direct axis and a quadrature axis. The increase or decrease in size may be governed by a systematic progressive series.
Claims
exact text as granted — not AI-modifiedThe invention claimed is:
1. A synchronous reluctance machine with or without permanent magnet assistance having a plurality of poles and comprising:
a stator with a plurality of spaced slots; and
a rotor comprising a plurality of flux barriers, each extending towards a circumference thereof such that a middle axis of the flux barrier intersects the circumference at a barrier point, the rotor having one direct axis and one quadrature axis for each pole;
wherein successive angular separations between barrier points around the circumference of the rotor increase following a geometric or arithmetic sequence or decrease following a geometric or arithmetic sequence when moving around half a pole pitch from an initial axis to an adjacent finishing axis, the initial axis being one of a direct axis and a quadrature axis and the finishing axis being the other one of the direct axis and the quadrature axis.
2. The machine of claim 1 , wherein the sequence is calculatable as though there is an additional barrier point at the initial axis and/or finishing axis, so that the angular separation from the initial axis to a first barrier point is treated as the first term in the sequence and/or the angular separation from the last barrier point to the finishing axis is treated as the last term in the sequence.
3. The machine of claim 1 , wherein the sequence is calculatable on the basis that the angular separation between the last barrier point of one half pole pitch and an adjacent last barrier point of the next half pole pitch is treated as the last term in the sequence.
4. The machine of claim 1 , wherein the first term of the sequence is chosen as
a
=
k
i
p
N
s
where a is a fraction of one pole pitch, k i is a constant, p is the number of poles and N S is the number of stator slots.
5. The machine of claim 1 , wherein successive angular separations moving from the initial axis to the finishing axis follow an arithmetic sequence such that there is a common difference, d, in size between successive angular separations.
6. The machine of claim 5 , wherein the sum of angular separations as a proportion of one pole pitch where there are n b barriers per half pole, and the presence or absence of extra barriers at the initial axis or finishing axis of the barrier sequence is signified by the Boolean variables, E i and E f respectively, is given by
Pole
Pitch
=
2
∑
k
=
0
n
b
(
a
+
kd
)
-
(
1
-
E
i
)
(
a
)
-
(
1
-
E
f
)
(
a
+
n
b
d
)
=
(
n
b
+
1
)
(
2
a
+
n
b
d
)
-
(
1
-
E
i
)
(
a
)
-
(
1
-
E
f
)
(
a
+
n
b
d
)
.
7. The machine of claim 1 , wherein successive angular separations moving from the initial axis to the finishing axis follow a geometric sequence such that there is a common ratio, r, in size between successive angular separations.
8. The machine of claim 7 , wherein the sum of angular separations as a proportion of one pole pitch where there are n b barriers per half pole and the presence or absence of extra barriers at the initial axis or finishing axis of the barrier sequence is signified by the Boolean variables, E i and E f respectively is given by:
Pole
Pitch
=
2
∑
k
=
0
n
b
(
ar
k
)
-
(
1
-
E
i
)
(
a
)
-
(
1
-
E
f
)
(
ar
n
b
)
=
(
2
a
1
-
r
(
n
b
+
1
)
1
-
r
)
-
(
1
-
E
i
)
(
a
)
-
(
1
-
E
f
)
(
ar
n
b
)
.
9. The machine of claim 1 , wherein the initial axis is a direct axis and successive angular separations between barrier points increase moving around the circumference of the rotor towards a quadrature axis.
10. The machine of claim 1 , wherein the rotor is transversely laminated, and the flux barriers are provided in each lamination.
11. The machine of claim 1 , wherein the flux barriers are formed as slots in the rotor.
12. The machine of claim 1 , further comprising permanent magnets located within some or all of the flux barriers, all orientated with the same polarity directed to a quadrature axis.
13. A rotor for a synchronous reluctance machine having a plurality of poles, the rotor comprising a plurality of flux barriers, each extending towards a circumference thereof such that a middle axis of the flux barrier intersects the circumference at a barrier point, the rotor having one direct axis and one quadrature axis for each pole, wherein successive angular separations between barrier points around the circumference of the rotor increase following a geometric or arithmetic sequence or decrease following a geometric or arithmetic sequence when moving around half a pole pitch from an initial axis to an adjacent finishing axis, the initial axis being one of a direct axis and a quadrature axis and the finishing axis being the other one of the direct axis and the quadrature axis.Cited by (0)
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